To be perfectly honest I use Lazarus, MameWAH, and EmuTron, and the reason I do is because the three authors frequent these boards and are amazing about helping work out problems and tech issues. I've asked questions about Lazarus and EmuTron and got answers back in hours, it was awesome (never had to ask about MameWAH it's wicked simple, my only wish is that I could make a use defined list of some sort or use a clone instead of the original in some cases).
I voted for MameWAH on the pole simply because it's the FE that I'm using on my half-a-cab right now. I think until the new versions of all three come out in the next month or so it's going to stay like that just because it's so easy to use and it runs games so fast. I would probably be using lazarus the majorty of the time but on large games it simply won't load them and on most small games it take up to 30 seconds to get them started (that doesn't sound like much but my mame box is top of the line and nothing should take that long). If you can get that worked out Howard, or if I'm doing some wrong, I would love to keep using it since I've made my own skin and all.
Anyway, I just wanted to say that I think all three FE's are great and I commend all three of the authors for their dedication to those of us that benefit from their hard work.
Thank guys,
-Niko