Personally, I stick to either A2 or A1 stocks. I dislike the rattle of the telestocks and their relative flimsiness.
Losing the ability to carry an always-available cleaning kit isn't a good idea, either.
I understand about the entry stock's niche. It exists, but not a use I'm ever likely to see.
One final note. (And no flame to anyone.) I would never attach a stock extension which obscured the butt-stock trap door, and which was not a slip-on/off design. In other words, NO SCREWS. Gotta be able to access the cleaning kit without looking for and fumbling for tools.
Picture this: You're in a fight, and your AR has a case head separation, or gets a good, solid barrel obstruction. Whatever, you need the cleaning rod NOW. You fumble for the butt stock trapdoor latch, only to remember with a sinking feeling in your gut, that it's covered by a screw-on extension/pad.
The bad part hits home when you realize that the Phillips head screwdriver/ Allen wrench, whatever, well, you've LOST it. Maybe that's not all you're gonna lose, either.