I have 2 cellphones Moto rokr Z6M / Iphone 3G(s) And 2 VoIp lines 1 of them is a 1800 number the other is a local that the 800 num is forwarded 2.
all of the three I am using, HTC mobile, landline -- you can take the brandname beetel as receiver and skype i use as a voip
I have used both of them. Laniline is for our my home use. But cell phone is more helpful when we are out of the home. In my opinion Land line is more helpful than cell phones.
I use HTC Touch cell phone with prepaid service from Smart. Landline from PLDT and cheap VoIP service from Onesuite.com