>>>Jay,
>>>I have VFP5,6,7,8,9 installed + .Net 2.0,3.0. Work with pure VFP, half VFP half .Net, pure .Net applications some of which share the same VFP data and no problems so far.
>>>PS: However if that application is small and you'd take the conversion step then I suggest taking the conversion step to SQLserver too (express is for free, remember).
>>
>>Or, VistaDb. It is very reasonable and does not require a server version. www.vistadb.net
>>Tim
>
>Guess I would stick with SQL Server as this is the first I've heard of VistaDB. From what I know so far, .NET was written to work seamlessly with SQL Server - I would rather stick with the status quo.

All other things being equal I'd go for SQL Express (or greater). Amongst other benefits using the SQLOLEDB provider knocks out a couple of data access layers, allows the use of named parameters and the CommandBuilder - and you can even write SQL SPs using the .NET CLR ! But since you have other apps using the VFP tables then just stick with them...