i agree wholeheartedly! in fact, i once had a 510 as my only pv...for about 4 days.
after which, i was very happy with my Egos/Rivas until i got my Echo 1300...i'm now so spoiled with its capacity and battery life, i can't imagine ever going back.
i also use an Ego pass-through to help conserve the overall battery life of my Echos (for those who don't know what an Ego pass-through is, it's an Ego battery that you can plug into your computer so you can vape your brains out without ever having a dead battery!).
and btw, i am far from rich...i purchased my stuff over several months, out of my "pv's and supplies budget," which was for half the amount i'd usually spend on analogs, and put the other half in a savings account...and this month, for the first time ever, i FINALLY didn't "need" anything new, so i took June's pv money and my savings and bought myself an adorable Yorkie pup.