I have and run Taran Tactical +1 and +2s. They run great and the extra rounds are worth having in my opinion, but I also think they are way too expensive for what they do.
I really like the +1 in terms of feel and practical fit for deeper concealment, though strongly preferred the feel of the Glock plates. I experimented with TT +3s, but the length of the extension and spring is just long enough to catch the follower on the seam of the mag body and extension and can cause malfunctions. Even if this almost never happens, it can (even on the TT-built version), which disqualifies it from carry use as far as I am concerned.
Taran Tactical accidentally sent me a double order of ten G43 magazines, but a) I wanted to do the right thing; and b) I don't like them enough to have kept the free ones, so I called them and they had me ship the extras back.
I was looking forward to ETS mags, but they did the same as Glock did and went and made a 6-round flush-fit mag, which is mind boggling. The ETS 9- and 12-rounders might be okay for reloads. The 9-rounders will probably be the sweet spot in terms of not having a novelty, stick length reload.
Glock was stupid not to make a 7-rounder, and so far, I think the aftermarket has still managed to miss the mark on bringing out a 7-round, flush fitting solution. I like Magguts in the G42, but unlike their G42 springs, they went with the G43 solution that doesn't play well with other extensions. That said, if one doesn't want an extension, I think Magguts in a standard Glock mag is the way to go. Or the Pearce +1 if wanting an extra finger on the grip, or the Vickers for +2. Time will tell, but the ETS 9-round mags may be the way to go for reloads and will cut down on cost and cobbling.