Hi Graciano and welcome to GoY. Sorry we are gardeners and couldn't possibly advise you if a particular vegetable is show worthy. To the best of my knowledge all the horticultural shows take place in summer so, I'm sorry to say, there is not were for you to exhibit it at the end of October.

I'd never heard of tromboncino - its also known as summer squash apparently. Loads of images of enormous ones on line... but Moon Grower is right, its too late for vegetable shows/competitions.

Here in Bracknell, we had our Marrowthon on Saturday for pumpkins, marrows and squashes.

Ah,well I did google vegetable shows in Bristol,but didn't find anything for this time of year. Check your local paper to see if there's any, Graciano.

I thought that all veggie shows were in September but maybe enthusiasts do have specialist shows for marrows etc. later in the year as said by Andrew.
As a recently retired show organiser I can say that the success of the show depends on all the entries by willing exhibitors. If you are impressed with the size of your vegitable then take it along and exhibit it. The organisers will welcome you and the public be impressed.Who cares if it wins 'best in show' or not, you gain brownie points for the effort.