Since fees are equal for both leased and bought equipment, the logical tipping point is return on investment with buying vs the size of the lease fee for leasing.
My first ViP622, the lease fee was $200. If I had bought it, I would have to sell it (assuming I paid $450 for it in February of 2006) for $250 to break even. Right now they are selling for about $200. I'm $50 in the hole if I buy.
My 211 had a lease fee of $50, so I'd have to have depreciation of less than $50 to break even - not likely.
My 211k had a lease fee of $25, even less likely to beat the depreciation bug.
Lastly, my 722k which I upgraded to from the 622 last month - no lease fee, just $29.99 for the OTA module. Absolutely no way buying can beat the $30 of depreciation over time on this deal.
Looks like leasing, at least for me is much better than buying.
YMMV.