Okay - I found that I come from a very different perspective than most "menthol" vapors and ex-smokers that will respond to this question here and in the rest of the "Forum" . . . Particularly, since I am a "Kool" Analog Fan and have been searching for that one "True Menthol tobacco" Flavor for over a year since I have been here . . . AND - While I have had many people make some wonderful suggestion and have been more than kind enough to share samples with "Me" - I still have not found the one - For "Me" . . . 
So - Even with that being said and until I do (Which is being worked on by a Very Dear Close ECF "Friend" who DIY's) - Here is some information for Ya' and "Your" friend - THAT IS ALL BASED - on "My" Experience and "My" OPINION (and of course for others it may be different
) . . .
First of all - as with most Analog Cigarettes the "Nicquid" - "Menthols" - are not created the same at all, especially when it comes to "Menthol" and their analog counterparts . . . Kools are not Newports - Newports are not Salems - Salems are not Marlboro/Winston Menthols - etc. (Hopefully "You" get "my" Drift
) . . . Nor are most of the "Nicquids" out there . . .
AGAIN - From "My" personal experience in the search for what "I" consider a "True Menthol" . . . The "Menthol" Nicquids can either be "strong" or "lite" . . . Can sometimes be very "Sweet" tasting, usually because of the type of "Menthol" they use - Mint, Spearmint, Peppermint . . . Or can be almost "Medicinal", like Toothpaste or Mouthwash or even a Halls Cough Drops (Which I also "like" - as if people wouldn't probably know that already
). . .
So depending on what analog's your friend smoked would be very important . . .
"You"/Your Friend will find many "Nicquids" that are similar or at least very close to Newports (especially Newports)/Salems/Marlboro/Winston Menthols out there that should be satisfying enough to assist them "Transitioning into the vaping World' if that is what they smoked . . .
Matter of fact, here are a couple of links to threads about "Menthol" suggestions for reference that might help (BTW: I have tried most, if not all of them
- They were just not for "Me") :
1) http://www.e-cigarette-forum.com/forum/new-members-forum/206047-you-menthol-folks.html
2) http://www.e-cigarette-forum.com/forum/general-e-liquid-discussion/233705-menthol-juice.html
3) http://www.e-cigarette-forum.com/fo...t-nice-menthol-but-no-tobacco-any-advice.html
Also, might I suggest checking out the ECF Sub-forum General E-Liquid Discussion and "Search" for "Menthol" (I retrieved over 200 pages of info there) . . .
Last - but not least - there are 2 products out there too that you/your friend might want to consider using . . .
First is "Menthol Crystals" (in liquid form) with a caveat - BE VERY CAREFUL USING - It is very Strong when made correctly - Only 1-2 drops in a "cartomizer"/"tank" . . . Or like "Me" - they may just find themselves on the floor trying to get their lungs back into their bodies after they get up - NOT A NICE EXPERIENCE AT ALL - but a lesson learned quickly . . .
NOPE - NA DA - NOT HAPPENING AGAIN . . . 
Second is "Kolada" - adds a GREAT REFRESHING Coolness to any "Nicquid" both on the inhale/exhale (Well as far as I am concerned) . . . However, again - Only 1-2 drops at a time in a "Cartomizer"/"Tank" . . . Just Sayin'' . . .
Both of these have been somewhat helpful for "Me" And I use them regularly with the 2 "Flavors" I have found so far and until I find THE ONE "True Menthol Tobacco" that will assist "Me" into the Vaping Full-Time and hopefully quit smoking analogs . . .
I do hope this information is helpful . . .
So - Even with that being said and until I do (Which is being worked on by a Very Dear Close ECF "Friend" who DIY's) - Here is some information for Ya' and "Your" friend - THAT IS ALL BASED - on "My" Experience and "My" OPINION (and of course for others it may be different
First of all - as with most Analog Cigarettes the "Nicquid" - "Menthols" - are not created the same at all, especially when it comes to "Menthol" and their analog counterparts . . . Kools are not Newports - Newports are not Salems - Salems are not Marlboro/Winston Menthols - etc. (Hopefully "You" get "my" Drift
AGAIN - From "My" personal experience in the search for what "I" consider a "True Menthol" . . . The "Menthol" Nicquids can either be "strong" or "lite" . . . Can sometimes be very "Sweet" tasting, usually because of the type of "Menthol" they use - Mint, Spearmint, Peppermint . . . Or can be almost "Medicinal", like Toothpaste or Mouthwash or even a Halls Cough Drops (Which I also "like" - as if people wouldn't probably know that already

So depending on what analog's your friend smoked would be very important . . .
"You"/Your Friend will find many "Nicquids" that are similar or at least very close to Newports (especially Newports)/Salems/Marlboro/Winston Menthols out there that should be satisfying enough to assist them "Transitioning into the vaping World' if that is what they smoked . . .
Matter of fact, here are a couple of links to threads about "Menthol" suggestions for reference that might help (BTW: I have tried most, if not all of them
1) http://www.e-cigarette-forum.com/forum/new-members-forum/206047-you-menthol-folks.html
2) http://www.e-cigarette-forum.com/forum/general-e-liquid-discussion/233705-menthol-juice.html
3) http://www.e-cigarette-forum.com/fo...t-nice-menthol-but-no-tobacco-any-advice.html
Also, might I suggest checking out the ECF Sub-forum General E-Liquid Discussion and "Search" for "Menthol" (I retrieved over 200 pages of info there) . . .
Last - but not least - there are 2 products out there too that you/your friend might want to consider using . . .
First is "Menthol Crystals" (in liquid form) with a caveat - BE VERY CAREFUL USING - It is very Strong when made correctly - Only 1-2 drops in a "cartomizer"/"tank" . . . Or like "Me" - they may just find themselves on the floor trying to get their lungs back into their bodies after they get up - NOT A NICE EXPERIENCE AT ALL - but a lesson learned quickly . . .
Second is "Kolada" - adds a GREAT REFRESHING Coolness to any "Nicquid" both on the inhale/exhale (Well as far as I am concerned) . . . However, again - Only 1-2 drops at a time in a "Cartomizer"/"Tank" . . . Just Sayin'' . . .
Both of these have been somewhat helpful for "Me" And I use them regularly with the 2 "Flavors" I have found so far and until I find THE ONE "True Menthol Tobacco" that will assist "Me" into the Vaping Full-Time and hopefully quit smoking analogs . . .
I do hope this information is helpful . . .