We've used the Lynx bus from TTC to SW. It was just fine. It runs twice an hour...check the schedule either online or when you get to the TTC. The bus was clean. It is Orlando's public transit, so you need to keep that in mind. It is not Disney transportation. We found that there were a lot of CMs heading off property at the end of their overnight shift on our bus.
You do have to mention to the driver that you are going to SW when boarding the bus though. It isn't a regular stop...if no one tells the driver they are going to SW, the bus won't stop there. When you get off the bus, at SW, you will cross the parking lot, at the lot street entrance.
When it's time to head back to WDW, head back across the parking lot, cross the street and head to the left. The bus stop is about 20' down the road. But be sure you know what time the bus is due. You don't want to just assume the bus will be coming, only to find that it doesn't stop there that late.