I've had 3 since I moved to the Caribbean. The first two (GreenDot in Trinidad and CaribServe in St. Maarten) use Motorola's Canopy system. Latency was never an issue and I consistently got the advertised speeds. Supposedly the technology can support 14Mbps (or more I'm told) but that was never offered by the ISP. In Trinidad I only got 512Kbps (US$200/month) and in St. Maarten I got 1Mbps (US$80/month) . Here in the DR I was hoping to get 5Mbps DSL but the phone company hasn't run any phone lines to our community, not sure if they ever will since everybody uses mobile phones. My only choice was WiMax from TriCom. Again, the technology can support rather high speeds but they only offer up to 1.4 Mbps service (US$145/month). Although not an issue, my ping times with TriCom are typically around 120ms. Not sure if that's related to the technology. Skype works just fine and has with all WISP's I've had.
From a convenience perspective, nothing beats wireless. With the Canopy system, I had to have a directional antenna aimed at the transmitter. With WiMax it's very simple. I have a small unidirectional antenna that just plugs into the electrical outlet and has an ethernet port. No configuration required at all.
Was hoping to get some feedback from anyone that has had a WISP. Have you been happy with the service? Are you getting the advertised speeds?
And a question directed to anyone that wants to chime in: Do you think WISP is the future or will it remain a niche market?