Me too, I thought I would find many tick off topics on this issue but you are the only one I seen. I used to love to play on her tab but since the update I just stay put on my epic.
It's probably a YMMV thing because of some bugs in the update that cause incompatibilites with apps/custom configurations installed on specific users' tabs. Also, I noticed my quadrant benchmark scores went up (significantly) after the update [see results below for various SGT models], which is strange since the hardware did not change (I can see a change due to graphics driver changes associated with the GB update - but not this much). This indicates that performance actually improved on my Sprint tab after the update. Could be a bug in Quadrant - who knows. While its hard to qualitatively say that my actual post-update performance improved, I can say that I am not experiencing any noticeable degraded performance (lagginess, choppiness, or charging issues) that others have reported.
Quadrant Benchmark Score Comparison (Avg after several runs)
WiFi Only SGT: ~700 (expected with weaker Proc and GPU than 3G models)
TMO SGT: ~930
Sprint SGT (after EF17 GB Update): ~1300
(I believe my Sprint SGT pre-GB update scores were around the same as the TMO's)