I have used G5 in the past with pretty amazing results. It catapulted our websites to the #1 lead source across the portfolio, as well as immediately produced leasing results (we had 2 online leases within the first 48 hours of launching the new websites). We also chose the unlimited marketing calls so we could track anything and everything and all phone calls were recorded - which was a huge help in leasing training. it is well worth the money and many companies that have used them - including ours - have been able to drastically cut back their marketing spending on other outside sources.
I used G5 for several websites in the past. Choices were somewhat limited, but set up and implementation was quick and painless. On par with other companies I've used for multifamily websites- superior for storage facility websites.