1) Sure! The Slow Stick can handle a couple of extra ounces.

2) You can, but be prepared to wait several hours each time. This will work for both 7 and 8-cell packs. The only problem is, you won't be able to tell when the battery is charged; you can only guess.

3) You should have no trouble with the Slow Stick. It's a little different from the Gentle Lady in that it's powered, but otherwise, control is the same.

4) If you want to get R/C flying banned in your town, and give the hobby yet another black eye, go ahead and try flying that Avistar in the local park. Larger electrics, and glow powered planes should only be flown where there is plenty of space, AND you have permission to fly. This will probably mean that you have to find a local club, then join it and the AMA. Then again, you could always procure develop your own flying site, but if there's one established in your area, such a task is both penny and pound foolish.