Altman still makes and sells a lot of
360Q's. They list for about $120 less than a Source 4 so it's a good choice when money is tight. There's nothing wrong with them, it's solid older technology. Grog's numbers are a close approximate but they aren't exactly correct. A 4.5X6.5 is 47 degrees, 6X9 is 34.3 degrees, a 6X12 is 24 degrees, 6X16 is 16.7 degrees, 6X22 is 11 degrees
This is a link to the download for their spec sheet. It has a nice little photometric chart in it to help you out.
Altman 360Q cheat sheet to calculate the size of the area of light:
For a 4.5X6.5 multiply
throw distance by: .88
For a 6X9 multiply
throw distance by: .62
For a 6X12 multiply
throw distance by: .41
For a 6X16 multiply
throw distance by: .29
For a 6X22 multiply
throw distance by: .19