Considering that geostationary orbits are 22,236 miles above the equator, that's your minimum distance to the satellite. If you're as far south as the Tropic of Capricorn (23.5 south), the satellite is a minimum of 22,906 miles away - assuming that it's at the same longitude that you are. If you're a ways off east or west, the distance to the satellite may be higher... so let's go with 23,000 miles - one way to the satellite.
To calculate your round-trip ping, realize that your ping packet has to travel:
- your station to the satellite (23k mi)
- satellite to network link (my guess is that's in North America, probably a minimum of 32 north; this is definitely over 23k mi)
- network link to ultimate destination (google.com?) - call this 10ms, though it'll be noise in the end
- google back to net link - 10ms
- net link to satellite (23k+ mi)
- satellite to your station (23k+ mi)
So what's that? 20ms + a minimum of 92k mi at 186k mi/sec... this will give you a minimum of 520msec ping round trips.
I used to have satellite up/down in Northern California - about 39N120W (2002-2006) via StarBand (don't know if they're around or not and too lazy to check)... I don't think I ever saw a ping rtt below 650ms anywhere in the net.
My experience with it at the time was that it was fine for casual use... click a link, a second later you had the page. It streamed fine at its given capacity (768k at the time). Interactive use was horrible, I had to replicate part of a testing lab at my location to be able to do development because typing remotely to a console was an exercise in predictive error correction. Upload was horrible at the time, I think it was 64kbps. That's plenty for web surfing, but sending binaries of any sort is prohibitive.
The high latency of course makes something like interactive gaming very challenging. Of course, I've seeing people playing WoW from OZ or South Pacific islands at 1500ms ping, so it's possible, but you do need to realize what you're getting into.
I assume that data rates have improved; of course, data files have increased as well.
Don't forget also that there are some serious data caps. StarBand at the time used a leakybucket approach; if you empty your bucket, you're not shut off, but if you keep pulling data non-stop, at some point you'll be limited to the resupply rate (which was 64kbps at the time....).
Given that you're going to be completely remote and far from any other possible internet connection, the caveats probably don't affect you - you don't have a choice. Satellite *will* work, but understand what you get.