trietwenty almost had it, but used he word 'more' and TRSS in the same sentence, which it certainly isn't
The salary is correct, as a TRSS SFO (in rough figures) you get £35,500 + £5,000 per year, which takes you to £40,500 (the same as a normal SFO, BUT...). Per month with sector pay in you will receive between £2,500 and £3,200 and this includes £416 for the TRSS loan. From this you pay £460 to the bank for the TRSS loan. So the £5000 doesn't quite meet the loan repayment, you have to make up a further £600 a year out of your take home pay.
To cut a long story short, as a TRSS SFO you will have in your pocket between £2000 and £2700 / month. (£500 / month less than a 'normal' SFO, who also hasn't forked out for the rating, and may still get the FO loyalty bonus)
Don't forget that you will have to find nearly 3 months pay to support yourself during the type rating course, so it doesn't just cost £23000, more like £30000 by the time you factor in lost wages. Whichever way people try and spin it you get less, the only more is what it costs for the type rating
If you leave the company you don't get the £5000, true. But you do get paid around £45000 by the likes of BA as an FO on the 737 which means you get 'more'. As TRSS the only bond you have is to the bank, the only company loyalty is to the highest bidder.
Just the facts, not saying it is good or bad, make up your own mind about that.