Interesting thread.. why don't you just look at what ppl at your local track are using?
GTX- prolly the best stock speedy cause it has great punch.. of course the fact that they do only a few meets then start to go soft shouldn't phase you as you can always just buy a new one every month.
LRP- Very reliable but I have seen more than one do a funny 1/2 shut down about 4mins into a race... still goes fast but with 1/2 power. But seem very reliable.
VFS-1/Hara twister- Famous for plumes of smoke when not set correctly... you also have to spend $$$ for the programming unit, very old school.
GTB- I currently use one with a 4.5r. Have seen ppl have glitching issues and even a few go up in smoke but mine has been bullet proof. In brushed mode they offer an insanly low on-resistence so should be something special. pity its so big.
Sphere Comp- somked mine on 1st run but seem to generally be reliable just like other LRP speedies. Seems to lose punch after a few meets.
Keyence- My old weapon of choice. The best speedie I have ever had to program and seems to be very very efficent. Even with old packs and 24degrees timing on 7t motors runtime is still usually no problem. Put some friends onto this speedie and their dumping issues disappered overnite! Mayb not the punchiest stock speedie even with the freq super low (like 1hz) but my mates have been cleaning up at every meet here in oz with one so can't be too bad.