Its not the issues at MOT time that concerns me as to be totally honest I expect the average MOT guy isnt even looking at the cats just if the exhaust is blowing as does the car have any terminal rot underneath or are any bushes or track arms showing movement.
The real issue I have is the cost options:
Buy a correct to fit twin lamba drilled cat specific for model...around £200 ish with onlythe effort in removing the old 1 and fitting the replacement...hopefully a sensible mornings work and all fixed.
Or buy 2 new cats at around £150 ..add the cost of the welding in the 2 bosses which I cannot do then have twice the work fitting 2 new cats with the modification of the down pipes which could go horribly wrong.
Mind made up...new cat to fit specific model along with bits to fit...will order in the morning but many many thanks for sharing various views