Do you have problems w/ OS or OS&Informix?

Dear friends, (excuse me, if you read this message twice) I would like to help my friend in deciding which combination RISC server/OS used to run Informix 7.1 server to buy. The server will be used in Informix client/server environment by cca 40 concurrent users (clients will be 486SX). We have offers from Digital, HP, SUN, IBM and Siemens. We are concerned primarily about the reliability and stability of the operating system and of the combination of Informix/OS. So we are interested in experiences (positive or negative) with running Informix 7.1 OnLine on one of the following operating systems: Digital UNIX 3.2 HP-UX 10.0 Solaris 2.4 (SUNOS 5.4) AIX 4.1 SINIX 5.42 These experiences (I hope) will be interesting for more potential users, so posting to this group(s) will be good, but if you can, please, answer also by e-mail to the address: nemec@fmph.uniba.sk Thanks in advance, Richard Nemec (Faculty of Mathematics and Physics, Comenius University, Bratislava, Slovakia) P.S. Some additional info about prereqs: Estimated size of the database is ~2GB (later ~5-8GB). The application assumes large amount of data retrieved from database and many updates/inserts.