fix washer/dryer or buy new dryer?

hello

I have a diplomat apm8721 integrated washer dryer. The washing part works fine but the drying part is broken. An engineer believes that the programme timer is faulty (but cannot guarantee that a new one will fix the problem).

A new programmer with labour will cost approx £90.

i would like some advise on my best course of action, please.

the options are:
1. try a new programmer timer in the machine.
2. buy a new integrated washer/dryer
3. buy a tumble dryer and put it in my shed.

Is it true that condenser dryers are very poor at drying clothes and never truly get them dry?

is this a good machine WHITE KNIGHT 44AW Dryer (currys price £129.95) ?
or is it worth paying extra for this one WHITE KNIGHT 84AW (currys price £179.95) with a sensor?

thanks
Patrick