Complications are not that frequent.
IF you do your research and find a VERY VERY good doc (which will cost, the better the doc, the more it costs), then the odds of complications will lower.
Here's a good site (though canadian) that will provide information on ALL aspects of augmentations.
The different types of enhancements
The different procedures for insertion
The after care
contra-indications before and after
before and after pics
etc etc etc
AND a wonderful forum of lovely supportive women at all stages.
www.canadaba.ca
In your shoes, i would check this site out and look for similar in the UK.
Picking your doctor is the most important thing... never mind what he/she charges.
That said, the site will also help you by providing a list of the questions you should ask of potential doctors.
My personal experience..... pregnancy, labour and delivery were FAR WORSE than day surgery for an agumentation and the lil bit of discomfort following. This is the most common opinion.
Hope that this helps.
hugs