I have 3 of them for a youth team I work with. They are shorter in LOP but they have a closer pistol grip built so small hands and fingers can be placed properly on the trigger. With 2 3/4 dram 1 oz shells they are very low recoil.
Excellent choice you made. Did the same for wife three years ago. She loves the gun.
Now the next step: send the gun off to a competent gunsmith to have an adjustable comb installed and get a gra-coil unit installed. Replace the Browning recoil pad with a kick-eez or gooey unit, get the sporting clays unit- the pad without a toe. If nothing else use a band sander and remove the hard pointy toe on the browning pad.....women do not appreciate the toe of the pad digging into their chests. We replaced the full choke tube that came with the gun with a Browning Diana grade modified choke. The Diana grade are made by briley and seem to perform better than the original.
Wife's gun has a liking to #8 shot and she shoots 1 1/8"oz 1200 fps loads with no problem either up close or farther back.
New BT 99 can be very tight and difficult for women to open when new. You can help her out by opening and closing the gun each night while watching the ball game on TV.
Watch out she will be beating you soon.
had one several years ago for my daughter- she started shooting when in 6th grade a 12 g- I would highly recommend a Ken Rucker adjustable Bump-buster if she is at all recoil sensitive- that combined with the BT-99 micro and an adjustable comb was the ticket for us until she started shooting bunker and needed a O/U