Port / Recode really big and old C++Builder code to Qt or CLI/Mono

I need to remake some old C++Builder (6) project and make it for Linux/Windows.

The main and big project parts is

1. OPC Client (and some other clients)
2. Working with database (currently MS SQL) but maybe porting to another one like postgres is another task.
3. GUI Components for Tables / Reports / Graphics / Diagrams !

Another trouble is that I currently just got few month for it so.

So I want to ask : Were is better / easer to port it ? MinGW dll + CLR GUI ? Qt ? maybe U++ ?

I'd go Qt for a few reasons:

• cross-platform UI
• using QSQL and correct plugin, you could have code working for both MsSql and PostGre (smoother transition, easier for testing)
• Qt is well documented and easy to deal with, moreover it compiles with Visual, thus preventing cygwin / mingwin mayhem on windows