Out of all the mechs I've owned:
1.) Fallout Mods Mutant - The Good: Hits the hardest (for brass alloys) IMO, battery life is amazing, magnetic switch (no HOT switches even at .09 Ohms and lower), easily adjustable, flush firing switch (no need for a locking ring), stainless construction, threadings are smooth, and the biohazard symbol on it is just sick.
The Bad: Price point ($200+ is a bit extreme), no grip (slidey), limited battery venting, and it's got brass top and bottom caps (I have OCD and HATE constantly polishing BRASS!).
2.) V3 Flip - The Good: The fact that I can toss a KICK2 with an 18650 in it, easy locking for firing switch, easy adjustment, extremely beautiful engravings, gold plated contacts, great threading, very grippy, battery venting, and very customizable.
The Bad: Hot switching frequently (springs and ball bearings in the locking switch) at .1 Ohm and lower, and price point ($250+)
3.) Cronos - The Good: Floating top pin, easy locking mechanism, stainless steel construction, grippy, and telescopic.
The Bad: Constant hot switching, screws fell out of the locking area constantly, brass top and bottom, threads were kind of squeaky, price point ($180+), and it just felt cheaply made.
I know hot switching is usually a sign of a short. And I checked CONSTANTLY for shorts - no shorts to be found. I fired it with and without the top caps of the RDA's installed and it STILL hot switched (where the bottom firing button would burn or "bite" the user). I couldn't figure it out until I realized that my resistance was obviously too low for those mechs. Hence the reason I switched to the Mutant. Magnets are kings folks. Just get a decent mod that uses magnets instead of springs. AVOID THE MAGNETO!