310 vs 182 probably won't make a difference. I'd suggest you go for the 310 for slightly better job chances in some countries when you leave Maun. The companies here don't care about the types you've flown, just what the labour department say - it was only a few years ago we were all putting any 200hr pilot into any aircraft that needed a pilot.
Everyone falls into one of a few categories now:
1. You have less than 500hrs = you won't get a job. No exceptions.
2. You have more than 500hrs, have never flown a C206, C210, GA8 and have no turbine time = some companies will be interested but your options are limited and only getting worse as time goes on.
3. You have more than 500hrs and HAVE flown a C206, C210, GA8 and have no turbine time = your options are getting better and half the companies will be interested, some might even want to put you on a C208 straight away.
4. You have more than 500hrs, with turbine time but not on a C208 = you're not a common type and no one knows exactly what will happen when they apply for your work permit. Probably send an email to OAR and hope for the best.
5. You have more than 500hrs and have flown a C208 = you will be offered a job.
It's pretty straight forward really. You fall into a category and take your chances.....