If the stuff they were getting from the yanks was better than the home-built stuff, they accepted it with enthusiasm. Pragmatism tends to win over nationalism when your life is on the line.

That's not to say there wasn't a bit of self-recrimination involved over the fact that the US designs were frequently better. To quote an Alec Richardson, a Briton sent to the US on the matter of tank production after a few British vehicles performed disastrously in US testing:

"We have lost a lot of prestige over these poor lone derilicts. Finally, an I consider this most important. WE MUST MAKE A FIRST CLASS CRUISER AND LIGHT TANK AT HOME, however long it takes us. The new Cromwell should fill the interim, for, say, the next year or two, but WE MUST REGAIN OUR PRESTIGE"

It wasn't just a matter of pride, but also a matter of practicality. As long as the UK indicated that it knew what it was doing, it could better influence the American designs which were coming off the production line. If the UK demonstrably could not produce a good tank, why would the folks in Detroit or D.C. give much credence to the design changes that the UK wanted? In this, it wasn't grudging the Americans for having built all the good equipment, it was berating the domestic crowd for not doing it right themselves.

Of course, that's not to say that the British weren't justifiably proud of some of their own designs, though I do wonder what the general opinions were of an RAF pilot who may have gone from Hurricane to Kittyhawk to Spitfire to Mustang. That's not anything I have any knowledge of, though.

You seem to be suggesting that US weapons and equipment replaced British produced stuff on a wholesale basis. However, that was not the case. Much American automotive derived weapons, such as tanks, were adopted, with the Sherman, Honey and Grant being very popular and far better regarded than the contemporary less than reliable Crusader and Valentine tanks that were produced in Britain. Once a more reliable British tank was developed, the Cromwell (from the Centaur) and the subsequent Comet and Centurion, the US tanks were replaced. Some US armoured cars and personnel carriers were used, but they were balanced by the various Daimler and Humber armoured cars, as well as the various forms of Carrier. As far as actual weapons are concerned, the British SMLE, Bren, Sten and Vickers were never replaced by US weapons, although things like BARs were supplied to the Home Guard. Neither were the various British artillery pieces replaced by US guns. Although the US supplied Britain with 50 obsolete destroyers, Admiralty designs of warships, with the exception of the escort carriers, were used by the RN throughout the war, and certainly weren't replaced by US vessels. Although the RAF used large numbers of American aircraft, at first, they were very quickly replaced by British designs as soon as they were available, with the only real exception being the Martlet and the ground attack versions of the Kittyhawk. Some aircraft, such as the Lightning, the Buffalo and the Airacobra were used very briefly by the RAF through desperation. The Mustang was used, but were returned as soon as the Lend-Lease Act ended.