I too like the basic Nitty Gritty machine. It is cheap (I spent $100 on mine used), reliable (I have had it for about 5 years now and it is still working fine, and I am at least the second owner), and it does a good job at what it does, (which is to vacuum dry the records). If you use the NG as strictly a vacuum, and do all the scrubbing yourself, you many never need to upgrade. (Unless you require a motor to spin the platter for you while it drys the record, in which case get the VPI 12.6, you lazy bum!:-)
The only cavaet about the NG is that it tends to get hot when you do a big batch of records. (I believe that the VPI 16.5 does too, btw). If you don't mind doing a few at a time, (say less than half a dozen), and giving the machine time to cool down before doing another batch, it will work just fine for you. If you need to do dozens of records at a time, I recommend that you get a machine with a fan to cool the vacuum, like the VPI 17F, (which costs about $1,200!).
My two cents worth.
PS It is also nice that it is so small, that you can easily lift it to put it away under an end table, or in a cabinet. Unlike the Keith Monks which I am restoring, which is big and very heavy. (I need to find a small table with wheels so I can move it from its storage closet, to my living room. I might actualy sell the KM, as I am not thrilled with the size and weight of it!