informix 7.x or universal server purchase

Hi everybody, We are in the process of purchasing informix online 5.x server for hp-ux 9. 04 with informix 4gl. It would be helpful if u could share some experiences with me for my questions 1) we would be upgrading to hp-ux 10.x in the next 6 months and then plan for online 7.x server, what if we go in for the universal server now , will it run on both versions of hp-ux and do u see any performance problem ie at the time of migration or during development 2) what will be the cost factors. 3) we are currently using fourgen case tools , I have known that fourgen does not support development in online 7.x version, we are currently working on 5.x for development and 7.x for production. 4) i also have in mind that if we think of loading online 5.x on hp-ux 10.x we require some additional port. any thoughts about this. any suggestions would be highly appreciated thanks in advance!! Moses Lawrence