I think they will be worse.
The problem is that amongst a large part of the electorate, about 50%, the scrounger rhetoric works. That has come about in part because of out and out lies about the social security system from all of the media and all of the main political parties, but also because it plays on natural prejudices, just like you can use immigration and race to divide communities, you can use this. It has also come about because of a neo-liberal ideology based around competitive individuals, as well as a lack of understanding, or interest in the lives of those in the bottom economic 10-20%. This has led to middle class assumptions, such as work always being good for your health, or unpaid work is a necessary way for poor children to gain vital experience in stacking shelves. At its most extreme it believes benefit sanctions are good for you, Atos assessments are 'help' and attacks on claimants are 'support'. Both Labour and Tory share this rhetoric, as do a large section of the trade union leadership, along with many charities and many in the medical establishment.
Most of the change in attitudes towards social security occurred during the last Labour government, although the seeds were sown long before that. The fight to try and stop some of this shit is not about stopping the tories, not really, it is about changing public opinion about social security and more importantly jamming a fucking spanner in the works at every opportunity. Both of these things will be harder under a Labour administration that will be fighting a trench war with the right wing press to prove they aren't soft on benefits. People will get jobs, charities will be offered contracts, everyone will be bought off, the number of people found fit for work will start to rise again, use of workfare will increase, and no-one will even fucking notice like they didn't last time because Labour will lose their war with the Daily Mail and everyone will think they are the welfare party.
It will be no huge loss given their ineptness, but we will lose the charities, and the unions, and all the treacherous labour supporters who have opportunistically used the suffering of claimants to mount a pseudo-radical attack on the Tories, and who are now all falling quietly back into line behind Ed. Those groups will not be replaced by a bunch of right wing Tories pretending to support us. And instead of two toffs and a bungling fucking captain mainwaring like IDS running the show, it will be faceless, boring bastards like Rachel Reeves, who will love us to death with poverty, forced work and sanctions and will be a much harder target to hit. If the last five years have taught us anything its that both Tories, and the private sector they need to push welfare reforms through, are vulnerable to effective protest and will quietly make concessions. Labour wont, because they'll be helping us, and the guardian and the mirror wont write about poor people anymore.