16. What RWIN (TCP Receive Window) value should I use ?

The TCP Receive Window (RWIN) value depends on two main factors:

1. The speed of your internet connection (bandwidth).
2. The maximum anticipated latency on the line (pings).

There is a BDP (bandwidth * delay product) formula that gives the approximate RWIN you should use for a given throughput and latency...

The Analyzer and the Optimizer go a couple of steps further in optimizing RWIN:

3. The recommended values for RWIN are multiple of MSS
4. The recommended numbers use large unscaled RWIN values

After all those calculations, here is a very rough breakdown of the Analyzer recommended values... Assuming land lines (satellite should use larger RWIN values because of the high latency), and 1492 MTU:

511104 -- works for ~8 to ~30 Mbps
255552 -- 2 to 14 Mbps
127776 -- 1 to 5 Mbps
63888 -- works well up to ~2 Mbps.