There are no other options, DemandTools is a Requirement

As a Salesforce.com Partner for 10+ years and having done 80+ implementations, the dirty little secret no one talks about (be to relative to day-to-day operations, implementations, app adoption, re-implementation, any mass email or marketing platform adoptions) is data. Data is ugly. Data is hard. Data has no clean or easy answers. Data is constantly evolving. Data takes strategy, configuration controls, and commitment. No other tool (none!) allows the company using Salesforce.com to assess and address their data issues, which we all have, better. DemandTools features (Mass Impact, Mass Effect, Find ID, etc.) are unparalleled. DataLoader and native data tools do NOT do what really needs to be done to clean what you have and bring in new data from your webinar or mass email or trade shows, etc. in a clean and strategic manner. Salesforce will tell you to import it all as leads. Ha! Like users are going to do all the work to clean those records one at a time to convert properly. There are at least 10 issues with Lead Conversion that virtually guarantee you duplicate and lost data. Not bad data, LOST data. PeopleImport--while hard to initially set up--is critical to anyone in Marketing. While DemandTools is ridiculously expensive now you have to ask yourself if you will willingly and knowingly throw out your Salesforce licensing costs and marketing dollars because you did not budget for DemandTools (and a qualified person to use it). Find ID alone is worth it. Single table dedupe alone is worth it. I could assess anyone's data (and config for that matter) and blow 20 holes into why it's wrong and how DemandTools could fix it AND help maintain healthy data with JobBuilder, etc.